RV Import Cut cryptic error

when importing an EDL with RV Import Cut tool, I got this error:
" ‘<’ not supported between instances of ‘NoneType’ and ‘int’ "

so probably something is missing in the edl which should have been compared to an integer?

when clicking on Details it seems to be related to a summary or text report:
File “/Applications/RV.app/Contents/src/python/sgtk/baked/plugin/bundle_cache/app_store/tk-multi-importcut/v2.4.2/python/tk_multi_importcut/cut_summary.py”, line 915, in get_report
key=lambda x: x.new_cut_order,